Autonomous navigation algorithm based on star sensor and horizon sensor

Directly sensing horizon is simply and reliable based on the horizon sensor. The navigation precision is lower depended on horizon sensor mainly. In this paper autonomous navigation algorithm by using measurement information of star sensor and horizon sensor is presented. The high precision satellite motion model is presented firstly. On the one hand the measure information of star sensor and horizon sensor are used to determinate orbit parameters. On the other hand the measure information of horizon sensor is used to determinate orbit parameters. The paper present a new information fusion method of autonomous navigation algorithm by using both of the two methods based on EFK federal Kalman filter. The observation equation of two models is educed in detail. The results of computer simulation show that the proposed system can improve the navigation precision, robustness and reliability.